1. Field of the Invention
The present invention relates to a laminated bonding structure of thin plate members in which a plurality of thin plate members, which is used in such as an inkjet printing head and an electronic component, are laminated and bonded so as to be fixed, and an inkjet printing head using the laminated thin plate members.
2. Description of the Related Art
A laminated bonding structure in an inkjet printing head has been disclosed in JP-2002-096477 (see pages 4 and 5, FIGS. 1 through 3 and FIG. 7). In the structure, a plurality of nozzles, a cavity plate having pressure chambers formed in accordance with the plurality of nozzles and ink flow paths for circulating ink into the pressure chambers, and a piezoelectric actuator for giving pressure to ink in the pressure chambers in accordance with the pressure chambers are laminated through an adhesive agent. The cavity plate in the inkjet printing head is composed of a plurality of plates. The pressure chambers are formed in a base plate as the uppermost layer of the cavity plate on which the piezoelectric actuator is laminated. Throttles (apertures) connected to the pressure chambers respectively and being smaller in sectional shape than the pressure chambers are formed in the base plate so that oversupply of ink into the pressure chambers can be prevented when the piezoelectric actuator is driven continuously. Escape grooves smaller in sectional area than the throttles are formed in positions near to the throttles.
When the piezoelectric actuator is bonded to the base plate through the adhesive agent to laminate such a plurality of plates to produce an inkjet printing head, the adhesive agent passing through a narrow gap such as a mating surface between the base plate and the piezoelectric actuator is first attracted by a small sectional area portion larger in capillary force than a large sectional area portion. As a result, a surplus of the adhesive agent is first led into the escape grooves, so that the throttles can be prevented from being blocked with the adhesive agent.